pile_limit option - movement feedback "there are objects here" (trunk only)

Something that pops up in the newsgroup periodically, with <Someone>
inevitably pointing out the bit of code that the user needs to tweak,
about control of feedback when hero is walking across floor objects.
Implement new option ``pile_limit'' which allows user to set the point
at which the game switches from listing the objects to giving "there are
several/many objects here".  Default is 5, same as previous hard-coded
value (1 object gets listed via pline, 2..4 are listed in a corner popup,
5 or more objects yields a pline message instead).  Setting pile_limit
to 0 means no limit, so objects will always be listed regardless of pile
size.  Setting it to 1 effectively forces no listing since any non-empty
pile size is always at least that big, so can produce "there is an object
here" even though that's no briefer than a pline() to show one object.

include/flag.h

@@ -1,4 +1,4 @@
-/*	SCCS Id: @(#)flag.h	3.5	2007/02/16	*/
+/*	SCCS Id: @(#)flag.h	3.5	2007/04/26	*/
 /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -59,6 +59,7 @@ struct flag {
 #define NEW_MOON	0
 #define FULL_MOON	4
 	int	 pickup_burden;		/* maximum burden before prompt */
+	int	 pile_limit; /* controls feedback when walking over objects */
 	char	 inv_order[MAXOCLASSES];
 	char	 pickup_types[MAXOCLASSES];
 #define NUM_DISCLOSURE_OPTIONS		5

include/patchlevel.h

@@ -13,7 +13,7 @@
  * Incrementing EDITLEVEL can be used to force invalidation of old bones
  * and save files.
  */
-#define EDITLEVEL	38
+#define EDITLEVEL	39
 
 #define COPYRIGHT_BANNER_A \
 "NetHack, Copyright 1985-2007"